There have been many research achievements in vision technologies and some of them have become feasible for practical applications, such as face detection and recognition. At the same time, digital video cameras, especially the low resolution Web cameras (webcams), are made very cheap and have become largely available for daily applications in the price aspect.
Such cameras can be useful for home security. Many home security systems are already available in the market and installed in many homes. However, most of these home security systems do not include intelligent video surveillance, which is still far beyond the price range of average homes.
As digital television replaces conventional televisions, as digital video cameras become inexpensive and largely available, and as vision technologies become ready for video surveillance applications, the need for inexpensive security systems with intelligent video surveillance abilities is even more evident.